Neurological and Musculoskeletal Pathophysiologic Processes
Neurological and musculoskeletal disorders, collectively referred to as neuromuscular disorders, affect the neuromuscular system. They affect the muscles, the nerves controlling the muscles, and communication between these nerves and muscles. These disorders are primarily characterized by motor weakness and tired muscles that can progressively waste away.
Classifications of neuromuscular disorders
Neuromuscular disorders are categorized into four broad groups
• Neuropathies. Involves disorders affecting the peripheral nervous system or nerves outside the spinal cord.
• Myopathies and dystrophies. Includes disorders that affect the tone and contraction of muscles and tissues that control voluntary movements. Dystrophy is the wastage of muscles often caused by a genetic mutation.
• Neuromuscular junction disorders. These disorders affect the site where the nerve cells meet the muscles, blocking a signal from bridging the nerve to the muscle.
• Motor neuron diseases. Affects nerve cells within the spinal cord. The most common form of motor neuron disorder is amyotrophic lateral sclerosis.
Signs and symptoms of neuromuscular disorders
Symptoms include weak and rigid muscles, diminished or loss of muscular control, and numbness. People with these disorders can also experience sensory disturbances such as spasms, twitching, tingling, and pain.
Neuromuscular disorders are progressive in nature. This means that they get worse over the years. During the early stages, muscle wasting can be unnoticeable and painless. However, the muscles become weaker over the years and can cause cramping, stiffness, and chronic pain. Sometimes, they can result in joint deformities, tightened and frozen joints commonly referred to as contracture.
What causes neuromuscular disorders?
There are many different causes of neuromuscular disorders. However, most of them are genetic, meaning that they are inherited and passed down from parents to children or caused by a spontaneous gene mutation. Other neuromuscular disorders are autoimmune diseases resulting from poisoning, toxins, or tumors, while the cause of others remains unknown.
How are neuromuscular disorders Diagnosed?
There are various tests used to diagnose different neuromuscular disorders. Examples are the electrical tests commonly known as nerve conduction studies that measure nerves’ ability to conduct electricity and the electromyography used to test the health status of affected muscles. Other tests include blood tests and muscle biopsies.
Unfortunately, most neuromuscular disorders have no cure. Available treatment options focus on improving the symptoms to increase mobility and improve the quality of life. The most common and effective treatments include drugs, surgery, and therapy.
Medications such as immunosuppressive drugs are used to treat certain disorders, while anticonvulsants and antidepressants are used to manage pain. Also, some disorders can be corrected using different types of surgeries such as thoracic surgeries, neurological surgeries, and orthopedic surgery.
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